Bats 101

GENERAL BIOLOGY

Most bats eat insects, but there are also species that eat fruit, nectar, fish, and other vertebrates. Three species of bat drink blood, none of which are found in Canada. As the primary predator of night flying insects such as moths, beetles, and mosquitoes — Canadian bats can catch hundreds of insects in just one hour. In fact, bats typically consume between 30 to 50 per cent of their body weight in insects in a single night; a pregnant female can consume 100% of her body weight each night. Having a healthy colony of bats can protect gardens and crops from damage and pests.

Bats make up nearly a quarter of known mammal species and are second only to rodents in terms of diversity. And there may be even more out there! Bat species are still being discovered. In fact, we are currently at 1300+ and counting!. Most of this diversity in bats is found in the tropics. Bats have a wide distribution and can be found on every continent except Antarctica.

Moreover, bats come in all shapes and sizes.The Philippine Flying Fox (Pteropus vampyrus) is one of the biggest bats and can weigh one kg (2 pounds) or more, and has a wingspan of more than two metres. The smallest bat is the Bumblebee Bat (Craseonycteris thonglongyai) which weighs around two grams with a wingspan of ~170 milimetres.

Bats evolved between 54.8 and 65million years ago and are more closely related to people than rodents.

North America has 48 bat species, with 19 found in Canada. British Columbia has the greatest diversity of bats (16 species) among the provinces; eight of those species do not occur anywhere else in Canada. All bats found in Canada are fairly small. The biggest bat in Canada is the Hoary Bat (Lasiurus cinereus) which weighs 26 grams with a 40 centimetre wingspan. The smallest bat in Canada is the Tricolored Bat (Perimyotis subflavus) which weighs between four and 10 grams with a wingspan of 21 to 26 centimetres.

Bats consume a variety of insects, some of which are important agricultural and forestry pests. In other areas of the world bats are also important for seed dispersal and pollination. In the U.S. alone, it is estimated that bats provide insect control services worth a few billion per year.

LIFE CYCLE & ECHOLOCATION

"Blind as a bat" is an expression based on the myth that bats are blind. In fact, bats have great vision and rely on it for many aspects of their lives. To find prey, however, most bats rely on echolocation.

Bats, like dolphins, use high-frequency sounds to navigate and communicate. Bats send out pulses of sound and the returning echoes enable them to detect obstacles in their path. Their skill is such that they are able to avoid items as fine as a human hair. So much for the myth that bats get caught in human hair!

SPECIES PROFILES: CANADA’S BAT SPECIES

Learn more in this comprehensive list of Canada's bats.

@ Brock Fenton

The Big Brown Bat (Eptesicus fuscus) is a common species found in most of southern Canada, excluding Nova Scotia, Newfoundland and Prince Edward Island, hibernating in caves, mines and buildings. Their length is 11 to 13 centimetres with a wingspan of 28 to 33 cm. Their colour varies from tan to dark brown.

@ Cori Lausen

California Myotis (Myotis calornicus) is a common species found in B.C., hibernating in buildings, mines, caves and dead trees. They are seven to 10 cm in length with a wingspan of 22 to 26 cm. Their colour varies from reddish-brown to dark brown.

@ Brock Fenton

Tricoloured Bat (Perimyotis subflavus) is an Endangered species found in Ontario, Quebec, New Brunswick and Nova Scotia, roosting in buildings and large trees. They are seven to nine cm in length with a wingspan of 19 to 16 cm. The colouration of each hair is black at the root, then yellow, with brown tips.

@ Brock Fenton

Eastern Small-footed Bat (Myotis leibii) is identified as a species of Least Concern and found in southeastern Ontario and southwestern Quebec. This species of hibernating bat can be found in hilly, mountainous areas, deciduous or evergreen forests and open farmlands. They are seven to nine ce in length with a wingspan of 21 to 25 cm. They are golden-brown in colour.

@ Jared Hobbs

Fringed Bat (Myotis thysanodes) is a species of Special Concern and can be found in British Columbia. When they’re not migrating, they typically roost in mines, cliffs, forested areas and buildings. They are eight to 10 cm in length with a wingspan reaching to about 28 cm. Named after its stiff or ‘fringed’ hair, it’s pale brown,with dark brown ears.

@ Brock Fenton

Hoary Bat (Lasiurus cinereus) is a common species found in nine of the provinces and territories including: British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, Nova Scotia and Northwest Territories. This migrating species of bat can be found in coniferous forests. It is the largest bat known to Canada with a length of 13 to 15 cm and a wingspan of 34 to 43 cm. Its colouration is black with brown-grey fur and frosted white tips on its back and tail, and a yellow head and throat.

@ Brock Fenton

Keen’s Myotis (Myotis keenii) is a common bat species found in British Columbia which hibernates in dead trees, caves, mines and buildings. Their wingspan is 23 to 28cm and they are seven to nine cm in length and they have silky brown fur.

@ Brock Fenton

The Little Brown Bat (Myotis lucifugus) is an Endangered species despite being identified in all parts of Canada (minus Nunavut). It hibernates in dead trees, cliffs, mines, caves and buildings. Like its name, this species of bat is only six to 10 cm in length and has a wingspan of 22 to 27 cm. It is brown in colour.

@ Brock Fenton

Western Long-eared Myotis (Myotis evotis) is a common species of bat found in British Columbia, Alberta and Saskatchewan in mines, buildings, cliffs, dead trees and stumps, although may migrate short distances in preparation for the winter months. It has a length of four to five cm and a wingspan of 22 to 25 cm. It is pale brown in colour with a black face and ears.

@ Cory Olsen

Long-legged Myotis (Myotis volans) is a common species of bat in British Columbia and Alberta. When it isn’t migrating short distances, it can be found in mines, caves, and dead trees. It has a length of eight to 10 cm and a wingspan of 24 to 28 cm. It is typically dark brown in colour.

@ Brock Fenton

Northern Long-eared Myotis (Myotis septentrionalis) is an Endangered species and canbe found in British Columbia, Alberta, Saskatchewan, Ontario, Quebec, Nova Scotia, Prince Edward Island and New Brunswick, where it roosts in forests and buildings. Its length is seven to nine cm with a wingspan of 21 to 25 cm. It has large black ears and a yellow-brown body.

@ Brock Fenton

Pallid Bat (Antrozous pallidus) is a Threatened species of bat that can only found in the Okanagan Valley of British Columbia. This hibernating species can be found in cliffs, buildings, and bottoms of valleys at low elevations. It has a length of six to nine cm and a wingspan of 38 to 40 cm. It has a pale stomach, brown back, grey wings and a snout-like nose.

@ Brock Fenton

Eastern Red Bat (Lasiurus borealis) is a common species that can be found in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick and Nova Scotia. When it isn’t migrating to warmer regions in the winter, they can be found in deciduous forests. Its length is nine to 12 cm and has a wingspan of 27 to 33 cm. It is multi-coloured with yellow-red-orange and yellow-greyish.

@ Brock Fenton

Silver-haired Bat (Lasionycteris noctivagans) is a common species of bat found throughout British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick and Nova Scotia. It is a migratory species and roosts in mines, caves and dead trees. Its length ranges from nine to 11 cm and has a wingspan 27 to 31 cm. It is black/dark brown in colour.

@ Brock Fenton

Spotted Bat (Euderma maculatum) is a species of Special Concern and can only be found in British Columbia, although it occasionally migrates, roosting in cliffs and hillsides. It has a length of 12 cm and a wingspan of 25 cm. It can easily be identified by its three white spots on its black back and has the largest ears of any bat species in North America.

@ Brock Fenton

Townsends Big-eared Bat (Corynorhinus townsendii) is a species of Least Concern and can be found throughout British Columbia hibernating in mines, caves, buildings and cliffs. This species has a length of 10 cm and a wingspan of 29 cm. It is pale brown/black-grey in colour with two visible glandular swellings on its nose.

@ Cori Lausen

Western Small-footed Bat (Myotis ciliolabrum) is a common species found in British Columbia, Alberta and Saskatchewan in cliffs and mines. It migrates throughout the winter season. It is eight to 10 cm in length and has a wingspan of 24 cm. It is yellow-brown in colour with a black face.

@ Cori Lausen

Yuma Myotis (Myotis yumanesis) is a common species found in British Columbia, hibernating in buildings, dead trees and mines. Its length is four to five cm and has a wingspan of 24 cm. It varies in colour from dark brown to tan/grey.

@ Brock Fenton

Brazilian, or Mexican, Free-tailed Bat (Tadarida brasiliensis) is a species of Least Concern found in woodlands, caves, bridges and buildings in the Salt Spring Island of British Columbia. They are nine to 13 centimetres in length and have a wingspan of 28 cm. They are brown in colour with large square ears, a wrinkled upper lip, and a prominent tail.

WHERE DO BATS GO?

When it comes to finding a companion, bats really go the distance. In early August, male bats peruse caves and mines searching out spots to spend the winter and mate with females. On their search, bats span tens and potentially hundreds of kilometres between overwintering spots. But what happens after the love fest is a bit of a mystery to researchers. We’ve assumed they settle in for hibernation, however, bat banding recoveries show that bats still migrate well into the fall — up to 60 kilometres a night — suggesting bats may hobnob at multiple hibernation sites when the temperature dips before choosing their final resting spot for winter.